This invention relates generally to apparatus for sealing the annular interfaces between housings and relatively rotatable shafts extending from the housings. More particularly, the invention relates to protective members associated with sealing lips incorporated in such apparatus. Where external steel casings have been utilized for structural strength in seal assemblies, prior art has taught the molding and/or bonding of non-metallic members to the metallic structures for providing protective members or guards thereon. The guards provide mechanical protection of the particulate or fluid sealing lips associated with the sealing assemblies. The processes of molding and bonding not only involve extra manufacturing steps, but also involve added costs and handling of associated materials utilized in joining the non-metallic members to the metallic structures. In addition, prior art teachings of non-metallic guard members hve involved relatively inelastic materials of limited resilience, as, for example, either hard plastics or phenolic-resin impregnated fiber board.
Simpler and more efficient constructions of guard members are needed, wherein the materials thereof have greater resilience and are hence deformable and less subject to cracking. Simpler manufacturing techniques are also needed, wherein bonding of resilient materials to the metal structures is not required. The latter improved seal constructions and techniques would be particularly desirable for the mass production of seal assemblies involving non-metallic protective members.